Comment 47 for bug 1447038

are those images created with grub-n-iso persistent USB's? that will create differences in timing etc especially on 2nd and later boots. Atleast on vmware this issue seems to be a race issue in the systemd units.

I don't think syslinux vs grub should make any difference, I see the same issue on an installed system under Vmware. It just doesnt hang there, since there is no prompt asking for user input.